Inner tube for pneumatic tires



Mar. 27, 1923.

- 1,449,692 R.l\|A| g v y .INNERTUBE FOR PNUMATIC TIRES Filed oct. 12', 1922` Waag/f. g A

197 d' WX I Patented Mar. 27, 1923.` v

UNITED STATES VPATENT OFFECE.

l ROBERT NALL, OF OAKLAND, CALIFORNIA.

INNER TUBE FOR PNEUMATIC TIRES.

Application led October 12, 1922. Serial No. 594,162.

T0 all whom it 'may concer/rt.'

Be it known that I, ROBERT NALL, a citizen of the United States, and a resident of Oakland, county of Alameda, State of California, have invented a new and useful Inner Tube for Pneumatic Tires, of which the following is a specification.

My inventionrelates in general to pneumatic tires as used on vehicles or automobiles, and has reference more particularly to an improvement in inner tubes for such tires.

As heretofore practiced, the ordinary inf ner tube which receives the air pressure for supporting the cuter casing of the tire has usually been made of relatively thin rubber and adapted to receive a relatively high air pressure. In order that tires` equipped with suc-h tubes could properly function without 'unnecessary deterioration and abuse, it is necessary to maintain the inner tube infiated to a maximum operating degree which leaves the tire so hard that the vehicle does not ride easily; then again, owing to the wear and tear on the tire ingeneral, the tube is more or less abused, whichgives it a short life and lays it open to punctures and the like.

The primary object of my invention is to overcome the many disadvantages` of the customary inner tube by providing a tube which will .be unusually rugged and capable of withstanding abuses, and at the same time require only a moderate air pressure to supply the desired sup-porting medium.

The preferred constructionl of the invention is illustrated in the accompanying drawing, in which Figure 1 is a view in perspective of a section of my tube; Figure 2 is a transverse section of the tube as applied to an outer casing, with the casing on the tire rim; Figure 3 is a view in vertical section of a valve which l propose to use with the tube; and Figure 4 is a top plan View of the valve. i

A Referring now vto the drawing in detail, I propose to make the 4tube A of a relatively thick and rugged structure by forming the same with a circumferential treadI thickness as atB with vthe thickness extending into the interior of the tube with a crest as at C.V The circumferential thickness B is pre-- sented beneath the tread surface of the outer casing D4 and the sides E of the tube decrease in thickness from the thickness B t0 the inner' circumference F. Even so,

the thickness of the tube at its thinnest polnt is thicker than that of the ordinary tube. The inner circumference F is made quite thick with the thickness formed to correspond to thev space between the confronting sides G and H of the opening in the casing D.

When the tire is assembled with the tube within the casing the thickness F' lies Hush ofthe casing so that these part-s may Iset within the rim I.

From the above it will be readily seen that the thickness B on the tube will' practically prevent tacks, glass, or other im aling devlcesfrom puncturing the tire, a thoughin the case of a very long nail it may extend through the tube, if it went in at the proper length as is customary, having a relatively large internal recess (6) terminating flush with the button (7) which is presented through an opening inthe thickness F of the tube so as to enable air to be introduced into the tube, and with the button preventing-'displacement of the stem. Positioned' within the recess (6) is an abutment (8) which is threaded into the recess from the opening inthe button (7) so as to provide a seat for the c oil spring (9). The abutment is made .with an opening (10) sov as not to retard they introduction of air through the stem into the tube. The opposite end lof the coil spring (9) abuts against the under side of a plunger (11) vwhich is tapered as at (12) vand adapted to seat against the tapered shoulder (13) at., the upper termination of the recess (6). The recess (6) at the tapered shoulder (13) terminates in the relativelysmall recess (14) which extends to the top of the stem. The plunger (1 1) is made with a stem (15) which extends through the recess (14) and terminates in a square end (16). The influence of the spring (9), together with the air pressure within the tube,V holds the plunger (11) against its tapered seat (13) to prevent escape of air from the tube, and when air is to be introducedinto the tube 4with the termination of the sides G and H `used to turn the the customary lling valve is placed over the reduced end of the stem and the pressure ofthe air will unseat the plunger and'V permit the tube to b e lled.

Should dust or other; foreign matter get between the taper (12) of the plunger and its seat, -so that the valve is not properly seated, the valve cap, which should be made with a square hole to correspond to the square end (16) of the-stem (15) may be plunger around and clean the seat. i s

To hold the ,stem rigid and to make a tight fit, I proposeto counter-sink a recess in the thickness F of the inner tube around the opening through which the stem passes,

and to use a Washer (17) on the stem which is seated in the counter-sink and aloclmut- (18) on top of the washer. The top of the 20 lock nut should come flush with the rimland as the stem passes through the rim a second loeknut (19) may be used on the outside of the rim as is customary. The usual dustjcap .i

should also be used.

I claim: Y An `inner tube for Fpneumatic tires embodying in its construction a relatively thick rib like enlargement extending circumferentially around the'inside of the tire directly beneath the tread surface of the outer casing of the tire, the sides of the tube decreasing in thickness from said enlargement to the inner circumference of the tube, and the inner circumference of the tube formed With a relatively ythick enlargement corresponding to the space between the sides of the casing.

ROBERT N ALL.

opening in the inner circumference of the 

